ARK-500A Operators Manual Aug 2008

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Use this device properly and safely.

BEFORE USE, READ THIS MANUAL. This operator’s manual contains information necessary for the operation of the NIDEK AUTO REF/KERATOMETER Model ARK-500A. This manual includes the operating procedures, safety precautions, and specifications. This manual is necessary for proper use. Especially, the safety precautions and operating procedures must be thoroughly understood prior to operation of the device. Keep this manual handy to verify use whenever necessary. The device complies with ISO 10342 (Ophthalmic instruments-Eye Refractometers) and ISO 10343 (Ophthalmic instruments-Ophthalmometers). The dioptric powers are indicated with reference wavelength λd = 587.56 nm. There are no user-serviceable parts inside the device except printer paper. If you encounter any problems or have questions about the device, please contact NIDEK or your authorized distributor.

MEDICAL EQUIPMENT WITH RESPECT TO ELECTRICAL SHOCK, FIRE AND MECHANICAL HAZARDS ONLY IN ACCORDANCE WITH UL6060l-1 AND CAN/CSA C22.2 No. 601.1 20AT (This applies only to equipment whose power source is 100/120 Vac.)

CAUTION • United States Federal law restricts this device to sale by or on the order of a properly licensed practitioner.

Safety precautions In this manual, a signal word is used to designate the degree or level of safety alerting. The definition is as follows.

CAUTION • Indicates a potentially hazardous situation which, if not avoided, might result in minor or moderate injury or property damage accident.

Even situations that are labeled “ CAUTION” may result in serious injury under certain conditions. Safety must be followed strictly at all times.

I

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Usage precautions

Before use CAUTION • Do not use the device for other than the intended purpose.

NIDEK is not responsible for accidents or malfunctions caused by careless use.

• Be sure to read the manual prior to operation of the device to understand the safety precautions and operating procedures thoroughly. Using the device for purposes other than specified in this manual may cause unexpected malfunctions and/or adverse events. • Never disassemble nor touch the inside of the device. This may result in electric shock or malfunction. • Install the device in an environment that meets the following conditions. The following conditions must be maintained during use. Use conditions Temperature: 10 to 35 °C (50 to 95 °F) Humidity: 30 to 90% (Non-condensing) Pressure: 800 to 1060 hPa A place with low dust A place with little external light A level and stable surface free from vibration and shock If the device is not installed and used under the above conditions, the reliability of measured results is impaired, and malfunction may result. In addition, there is a possibility of injury if the device receives shock and falls down. • Avoid storing the device where it is exposed to rain or water, or poisonous gas or liquid is present. Corrosion or malfunction of the device may occur. • Avoid installing the device where it is exposed to direct air-conditioning flow. Changes in temperature may result in condensation inside the device or adversely affect measurements. • Be sure to use a (HOSPITAL GRADE) wall outlet which meets the power specification requirements. If the line voltage is too high or too low, the device may not perform properly. Malfunction or fire may occur. • Connect the power plug to a ground outlet. Or connect a grounding wire to a ground terminal. Electric shock or fire may occur in the event of device malfunction or power leakage. • Completely insert the power plug into the outlet as far as the prongs will go. Fire may occur if the device is used with a loose connection.

II

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CAUTION • Never use a power strip or extension cable to supply the device with power. The electrical safety may be lowered.

• Do not use a power cord other than the one provided. Also do not connect the provided power cord to any other device. Failure or fire may result. • Do not place heavy objects on the power cord. The damaged power cord may cause fire or electric shock. • Before connecting the cable, turn off the power switch and disconnect the power cord from the outlet. Malfunction of the device may result. • When the device is carried, two persons should hold it at positions (A) and (B) (both right and left sides). Avoid lifting by the forehead rest or main body instead hold it by the bottom of the base.. If only one person carries the device, or areas other than the base are used for lifting and the device falls, there is a possibility of injury or malfunction.

(A)

(B)

• To transport the device, use the special packing materials to protect the device from impact of dropping. Excessive vibration or impact to the device may cause malfunction. • In installation and operation of the device, observe the following instructions about EMC (electromagnetic compatibility): - Do not use the device simultaneously with other electronic equipment to avoid electromagnetic interference with the operation of the device. - Do not use the device near, on, or under other electronic equipment to avoid electromagnetic interference with the operation of the device. - Do not use the device in the same room with other equipment such as life-support equipment, other equipment that has major affects on the life of the patient and results of treatment, or other measurement or treatment equipment that involves small electric current. - Do not use the device simultaneously with portable and mobile radio frequency communication systems because it may have an adverse effect on operation of the device. - Do not use cables and accessories that are not specified for the device because that may increase the emission of electromagnetic waves from the device or the system and decrease the immunity of the device to electromagnetic disturbance. • The Electromagnetic Compatibility Directive sets the essential requirements for electrical and electronic equipment that may disturb, or be disturbed by, other equipment. The ARK-500A complies with these requirements as tabled on pages 107 to 110. Follow the guidance in the tables for use of the device in an electromagnetic environment.

III

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During use CAUTION • Before use, perform visual and operation checks. If abnormal conditions are encountered, stop using the device.

If the device is used under abnormal conditions, intended results may not occur. Also unexpected malfunctions or health hazards may occur due to improper measurement. • Be sure to connect a communication cable, checking the symbols of input (IN: and output (OUT:

)

).

Data transmission may not be performed properly. • Before treating each patient, clean the patient’s contact area (chin rest and forehead rest) with clean absorbent cotton or gauze dampened with rubbing alcohol. If chinrest paper is used, remove one piece for each patient. For severe stains, wipe the area not with a dry cloth but with gauze dampened with alcohol. • Keep the measuring window free of fingerprints and dust. The measurement accuracy may decrease substantially. • In the event of smoke or strange odors, immediately turn off the device and disconnect the power plug from the outlet. After you are sure that the smoke has stopped, then contact NIDEK or your authorized distributor. Usage of the device under such abnormal conditions may cause fire or electric shock. In case of fire, use a dry chemical (ABC) extinguisher to extinguish the fire. • Immediately replace the power cord if the internal wires are exposed, the device turns on or off when the power cord is moved, or the cord and/or plug are too hot to be held with hands. This may result in electric shock or fire. In the event of malfunction, disconnect the power cord from the wall outlet. Never touch the inside of the device and contact NIDEK or your authorized distributor. • Never press on the LCD with a hard object such as a ball-point pen. Keep magnetic objects away from the LCD. The device may be damaged. • Do not operate the LCD with wet hands. Water seeping into the device may result in failure of the device. • There may be a few dead or constantly-lit pixels in your LCD. This does not represent failure of the LCD; This is due to the structure of the LCD.

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CAUTION • This device has been tested and found to comply with the limits for medical devices to the IEC 60601-1-2: 2001/am1: 2004, and Medical Device Directive 93/42/EEC.

These limits are designed to provide reasonable protection against harmful interference in a standard medical installation. This device generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to other devices in the vicinity. However, there is no guarantee that interference will not occur in a particular installation. If this device does cause harmful interference to other devices, which can be determined by turning the device off and on, the user is encouraged to try to correct the interference by one or more of the following measures: If this device does cause harmful interference to other devices, which can be determined by turning the device off and on, the user is encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate the receiving device. Increase the separation between the devices. Connect the device to an outlet on a circuit different from that to which the other device(s) are connected. Consult the manufacturer or field service technician for help. • Never use the device with cables or accessories other than the designated ones. Malfunction caused by improper electromagnetic compatibility (EMC) characteristics may result. • Never use portable or mobile radio frequency (RF) devices in the vicinity of this device. These devices may adversely affect medical electrical equipment and malfunction may result. • If the instrument is connected to a PC that does not comply with IEC60601-1 (except one that uses an AC adapter that meets the Class II requirements of IEC60950-1), supply power to the instrument and PC through isolation transformers. Contact NIDEK or your authorized distributor for installing isolation transformers.

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CAUTION • Information on the avoidance of overexposure to potentially hazardous optical radiation (ISO 15004: 1997)

Spectrally weighted photochemical radiances LB and LA give a measure of the potential that exists for a beam of light to cause photochemical hazard to the retina. LB gives the measure for eyes in which the crystalline lens is in place. LA gives this measure either for eyes in which the crystalline lens has been removed (aphakes) and has not been replaced by a UV-blocking lens or for the eyes of very young children. The value stated for this ophthalmic device gives a measure of hazard potential when the device is operated at maximum intensity and maximum aperture. The values of LA or LB for the ARK-500A are sufficiently low as shown on the following page. The retinal exposure dose for a photochemical hazard is a product of the radiance and the exposure time. For instance, at a radiance level of 0.5 mW/(cm2•sr), 480 min irradiation of the dilated (8 mm diameter) pupil would cause the retinal exposure dose level to attain the recommended exposure limit. If the value of radiance were reduced to 0.1 mW/(cm2•sr), five times that time (i.e. 2400 min) would be needed to reach the recommended limit. The recommended exposure dose is based on calculations arising from the American Conference of Governmental Industrial Hygienists (ACGIH) - Threshold Limit Values for Chemical Substances and Physical Agents (1995 - 1996 edition). The following page shows the graph of spectrum output for the ARK-500A. Patients will be at low risk of acute optical radiation with the ARK-500A. However, it is recommended that the intensity of light directed into the patient’s eye be limited to the minimum level which is necessary for diagnosis. The total of the retinal exposure dose must be carefully watched for infants, aphakes and persons with diseased eyes who are at greater risk when other ophthalmic devices with a high level of radiance are used in conjunction. • Spectrum output of all light source during AR/KM measurement (maximum light intensity)

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* The wavelength 1000 to 1100 is calculated and plotted according to the wavelength characteristic data of the infrared LED used.

• Spectrum irradiance LA (mW/cm2/sr) 305 - 700 nm

0.397

LB (mW/cm2/sr) 380 - 700 nm

0.053

LA: Spectrally weighted photochemical aphakic source radiance LB: Spectrally weighted photochemical phakic source radiance

VI

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After use CAUTION • This device uses a heat-sensitive printer paper. To keep the printed data for a long period of time, make copies of the printouts.

The paper degrades over time and the printed data may become illegible. • When the device is not in use, turn off the power switch and put the dust cover over the device. If not, dust may affect the measurement accuracy. • Do not yank the power cord to disconnect it from a wall outlet but hold the plug. This can damage the metal core of the cord and may result in fire, short circuit or electric shock. • Occasionally clean the prongs of the main plug with a dry cloth. If dust settles between the prongs, the dust will collect moisture, and short circuit or fire may occur. • If the device will not be used for a long time, disconnect the power cord from the wall outlet. Fire may occur. • Maintain the surrounding temperature and humidity in the following ranges during transport and storage of the device. Environmental conditions Temperature: –10 to 55 °C (14 to 131 °F) Humidity: 10 to 95% (non-condensing) Atmospheric pressure: 700 to 1060 hPa A place with low dust A place not exposed to direct sunlight • To transport the device, use the special packing materials to protect from shock and impact. Excessive vibration or impact may cause device malfunction.

VII

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Maintenance and check CAUTION • Only service technicians properly trained by NIDEK can repair the device.

NIDEK is not responsible for any accidents resulted from improper servicing.

• When performing maintenance work, secure sufficient maintenance space. Maintenance work in an insufficient space may result in injury. • When the device is sent back to NIDEK for repair or maintenance, wipe the surfaces (especially, the area where patients contact) of the device with a clean cloth dampened with ethyl alcohol for disinfection. • Contact NIDEK or your authorized distributor to check whether the device needs measurement accuracy calibration if the AR-measured results are substantially different from subjectively measured results.

Disposal CAUTION • Follow the local ordinances and recycling regulations regarding disposal or recycling of the components.

It is recommended to commission the disposal to a designated industrial waste disposal contractor. • When disposing of packing materials, sort them by material and follow local ordinances and recycling regulations.

VIII

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{ Patient environment The patient environment represents a space where there is a possibility of direct contact between the patient or the operator and third person. When another type of device is used in the patient environment, use a device that complies with IEC 60601-1. If the devices that do not comply with IEC 60601-1 are used, it is necessary to use an isolating transformer as a power supply or to connect the devices to additional protective grounding.

Radius of 1.5 m

2.5 m

1.5 m

1.5 m

IX

Table of Contents 1. BEFORE USE... 1 1.1 Outline of the Device...1 1.2 Indications for Use...1 1.3 Principles...2 1.4 Configuration...3 1.5 Measurement Screen Layout...7 1.6 Labels...13 1.7 Checking Contents...14 1.8 Before First Use...15

2. OPERATING PROCEDURES... 19 2.1 Operation Flow...19 2.2 Preparation for Measurement...20 2.2.1 2.2.2 2.2.3 2.2.4

Checking the measuring window cleanliness at device start-up...26 Switching to manual mode...27 Sleep mode...28 Finishing the measurement...28

2.3 AR (refractive error) and KM (corneal curvature radius) Measurements: AR/KM Measurement Mode...29 2.3.1 2.3.2

Cataract measurement mode...37 Measurement ring image display...38

2.4 AR (refractive error) Measurement: AR Measurement Mode...39 2.5 KM (corneal curvature radius) Measurement: KM Measurement Mode...41 2.6 View Comparison Function...43 2.7 CS (Corneal Size) Measurement...47 2.8 PS (Pupil Size) Measurement...49 2.9 PD (Pupillary Distance) Measurement...51 2.9.1 2.9.2

Auto-PD measurement...51 Manual PD Measurement...51

2.10 Measuring Hard Contact Lenses...53 2.11 Printing...55 2.11.1 Printing measured data...55 2.11.2 Eyeprint...58 2.11.3 Printing parameter settings...59

2.12 Parameter Settings...60 2.12.1 Parameter tables...63 2.12.2 Setting the time and date...73

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2.12.3 Entering comments... 75

3. OPERATION WHEN PERIPHERAL DEVICES ARE CONNECTED... 77 3.1 Connecting to the NIDEK Motorized Refractor (RT) or Computer... 77 3.1.1 3.1.2 3.1.3

Outline... 77 Connecting procedure... 78 Operating procedure... 78

3.2 Connecting to the NIDEK Auto Lensmeter (LM)... 79 3.2.1 3.2.2 3.2.3

Outline... 79 Connecting procedure... 79 Operating procedure... 80

3.3 Connecting to the Eye Care Card System... 81 3.3.1 3.3.2 3.3.3 3.3.4

Outline... 81 Connecting procedure... 81 Transferring data with the EyeCa-RW... 82 Erasing data on the Eye Care card... 83

3.4 Reading Patient IDs... 84

4. MAINTENANCE... 87 4.1 Troubleshooting... 87 4.2 Error Messages and Countermeasures... 89 4.3 Replacing Printer Paper... 92 4.4 Fixing Chinrest Paper... 94 4.5 Checking the AR/KM Measurement Accuracy... 95 4.6 Cleaning... 97 4.6.1 4.6.2

Cleaning the measuring window... 97 Cleaning the printer... 99

4.7 List of Replacement Parts... 100

5. SPECIFICATIONS AND ACCESSORIES... 101 5.1 Classifications... 101 5.2 Specifications... 102 5.3 Standard Configuration... 105 5.3.1 5.3.2

Standard accessories... 105 Optional accessories... 105

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6. EMC (ELECTROMAGNETIC COMPATIBILITY)... 107 7. GLOSSARY... 111 8. INDEX... 113

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1. BEFORE USE 1.1

Outline of the Device

1

The NIDEK ARK-500A is an auto ref/keratometer which contains both a refractometer and keratometer in one unit. The refractometer objectively measures refractive errors of sphere, cylinder, and axis for lenses that correct the patient’s vision into emmetropia. The keratometer measures the corneal curvature radius (corneal refractive power), principal meridian direction and corneal cylindrical power. Refraction is mainly performed as a reference for lens prescription to correct the visual acuity using glasses or contact lenses. The corneal curvature radius measurement is mainly performed for the following purposes: • Lens prescription for correction of visual acuity using contact lenses or such. • Determination of the power of intraocular lenses to be implanted after cataract surgery. • Postoperative follow-up of corneal shape This device is a single unit with the main body mounted on a base. The base is provided with a chinrest on the patient side. The measuring unit is provided with an LCD panel, operating buttons, joystick, and printer to facilitate alignment and other operations. The device offers the following features in addition to the above features: • The ARK-500A is provided with an auto-tracking mechanism that achieves alignment in the up-and-down direction. • An auto-shooting function is provided; measurements to be taken automatically when the device is best aligned and focused. • A motorized up-and-down chinrest allows the operator to easily adjust the height of the chinrest. • A built-in RS-232C interface allows data export to computers and such. • A view comparison function and measurement ring image display function are provided.

1.2

Indications for Use The Auto-Ref/Keratometer ARK-500A is a medical appliance which performs measurement of the refractive errors of the eye, corneal radius of curvature.

1

BEFORE USE: Principles

1.3

Principles Fine measurement beams are projected on the fundus of the patient’s eye by a projecting optical system and then computation is performed by capturing the reflected beams as a ring image to measure the refractive errors (SPH, CYL, AXIS) of the patient’s eye. Calculation is also performed by capturing the mire ring projected on the patient’s cornea as an image to measure the corneal curvature radius (refractive power) and the principal meridian direction.

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BEFORE USE: Configuration

1.4

Configuration

{ Front view

1

Function buttons

LCD

Memory indicator

Start button

Locking lever

Joystick

Power switch

Cover open button Printer cover

Function buttons Set the device and switch the screen. Functions assigned to the function buttons are displayed by icons on the screen. Two buttons on the left of the screen have unique functions when the measurement screen is displayed. • Clear button (

)

Erases the measured data. When the clear button is pressed for about a second, all the measured data is erased.

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BEFORE USE: Configuration

• Print button (

)

Pressing this button when the memory indicator is lit, prints out the measured data. Pressing the button when the memory indicator is not lit, advances printer paper.

LCD 5.7-inch LCD. Pulling the bottom of the display panel provides an adjustable viewing angle. For measurement in a standing posture, set the panel at a suitable angle. The panel is reset to its original position by magnet.

Memory indicator Indicates that measured data is being saved in memory. ON

Being saved

OFF

Not being saved

Blink

Sleep mode

Start button When the start button is pressed, measurement is taken regardless of the alignment or focusing condition of the device. Joystick Used for alignment and focusing. Alignment in the side-to-side direction can be performed by moving the joystick to the right and left. Rotating the joystick is for alignment in the up-and-down direction. For focusing, move the joystick back and forth.

Locking lever Secures the main body to the base. To lock the main body, press the locking lever down.

Power switch Turns on the power to the device. Printer cover Inside is the printer equipped with the auto cutter located. Open the printer cover for replacing printer paper by pressing the cover open button. Cover open button To open the printer cover, press the button.

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BEFORE USE: Configuration

{ Rear view Forehead rest Eye level marker

1

Measuring window Chinrest up/down buttons

Chinrest

PD window

Forehead rest During measurement, the patient’s forehead should be gently rest against the forehead rest. Clean the chinrest for each patient.

Measuring window Check the window cleanliness before measurement. Chinrest Clean the chinrest for each patient. Eye level marker Used as a guide for the patient’s eye level during measurement. The height of the chinrest should be adjusted so that the center level of the patient’s eye almost aligns with this line.

Chinrest up/down buttons (

,

)

Move up or down the chinrest. PD window An LED is provided to detect the PD value.

• Parts that come into contact with the patient during measurement are composed of the following materials. Forehead rest: Elastomer Chinrest: ABS resin

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BEFORE USE: Configuration

{ Bottom view Power inlet

RS-232C ports

USB-A port

Power inlet Connect a detachable power cord. RS-232C ports Connect a communication cable to send/receive the measured data to/from a diagnostic device or such. Target device RT-1200 series, RT-2100 series, RT-5100 LM-500, LM-970, LM-990/990A, LM-1000/1000P, LM-1200

(OUT)

To export the measured data to the refractor (RT), an external computer or such, connect a communication cable to this side. The optional Eye Care card system is connected to this side.

(IN)

To import the measured data to from a NIDEK lensmeter, connect a communication cable to a lensmeter.

Connecting the lensmeter to the

side and the RT-2100/RT-5100 to the

side allows data transmission to

the connected refractor via the ARK-500A.

USB-A port Connect the optional barcode scanner. Do not connect equipment other than the barcode scanner. *1 Accessory equipment connected to the analog and digital interfaces must be certified according to the representative appropriate national standards (for example, UL 1950 for Data Processing Equipment, UL 60601-1 for Medical Equipment, and CSA C22.2 No. 601-1, EN 60601-1, and IEC 60601-1.) Furthermore, all configurations shall comply with the system standard IEC 60601-1-1. Anyone who connects additional equipment to the signal input part or signal output part configures a medical system, and is therefore responsible that the system complies with the requirements of the system standard IEC 60601-1-1. If in doubt, consult the technical service department or your local representative.

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BEFORE USE: Measurement Screen Layout

1.5

Measurement Screen Layout The screen for AR (refractive error) and KM (corneal curvature radius) measurements is comprised of pages 1 to 3.

1

Each page differs only in the touch icons displayed to the right of the screen. <When Page 1 is displayed> Auto-tracking indication Auto-shooting indication Patient’s eye

CYL mode

R/K button

CS/PS/PD button

Target Focusing indicator Auto button Manual mode button Minimum pupil circle Ring image enlargement button Mire ring Measured values

Page button

Patient’s eye Indicates the right or left eye of the patient. R/K button (

)

Selects a measurement mode in R/K measurement. Select from AR/KM measurement mode, AR measurement mode or KM measurement mode. The selected measurement mode is displayed on the screen. The measurement mode switches in the following order: AR/KM measurement mode (successive AR and KM measurements) → AR measurement mode (AR measurement)→ KM measurement mode (KM measurement)→ AR/KM measurement mode...

Target Used as a guide to locate the patient’s eye in the center of the screen. Align the mire ring projected on the patient’s eye with the target. Auto button (

)

Selects the auto-tracking function and auto-shooting function. Select auto-tracking from

(UpDown) or OFF. Select auto-shooting from ON or OFF.

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